1. Technical Field
The present invention relates to sheet material with IC tags.
2. Description of the Related Art
An example of a corrugated structure with IC tag labels adhesively attached is disclosed in U.S. Pat. No. 6,667,092. This conventional corrugated structure includes a second linerboard and a single-face flute that is comprised of a first linerboard and a corrugated medium. The IC tag labels are attached to one side of the second linerboard. Then the second linerboard is adhesively bound with the corrugated medium so that the IC tag labels are sandwiched between the second linerboard and the corrugated medium. In producing the corrugated structure with IC tags, the IC tags are handled in the form of IC tag labels. The IC tag labels are formed from a label sheet that includes a release liner, a label substrate, an adhesive layer that is disposed on the bottom surface of the label substrate, and IC tags that is positioned on the upper surface of the label substrate. After the IC tags are attached to the adhesive layer, by making cutting line on label substrate and the adhesive layer so that cutting line surrounds IC tags, IC tag labels can be removed from the release liner. The IC tag labels are attached to the corrugated structure according to the following steps. First, the label sheet is unwound from a reel. The unwound label sheet is moved downstream between two rolls that are compressing the label sheet. At the same time, each IC tag label is exfoliated from the release liner and attached to the predetermined positions on one side of the second linerboard facing the corrugated board. The label sheet, after the IC tags are removed from it, is wound into a roll. The positions to attach IC tags are determined based on the marks on the second linerboard read by a sensor.
The corrugator is a machine that has a large width (approximately two meters) and that is operated at high speed (200-300 meters per minute). One sheet of the sheet material is slit into several pieces in the cross direction. The same number of labelers as the number of the pieces is needed and the labelers need their own space. For making the space, the bulk corrugator, having a length of 100 meters or more, must undergo a large modification. The corrugator should preferably be operated at a constant laminating speed to keep the adhesive strength of corrugated board sheet and flatness of cut sheets. However, when the intermittent labeler disclosed in U.S. Pat. No. 6,667,092 is used without reducing the traveling speed of the second linerboard, mechanical troubles are likely to occur. Consequently, the IC tag may be attached to the sheet material improperly or the IC tag may be damaged. This means that IC tag loss occurs frequently. As the IC tag is expensive (several tens yen/IC tag), such IC tag loss increases the production cost of corrugated board boxes with IC tags. Spending the high production cost is not acceptable because corrugated board products are characterized in its cheep cost.